Ptilofenestella Tavener-Smith, 1965

Ernst, Andrej, Wyse Jackson, Patrick N. & Aretz, Markus, 2015, Bryozoan fauna from the Mississippian (Visean) of Roque Redonde (Montagne Noire, southern France), Geodiversitas 37 (2), pp. 151-213 : 190

Genus Ptilofenestella Tavener-Smith, 1965

TYPE SPECIES. — Ptilofenestella carrickensis Tavener-Smith, 1965 , by original designation. Mississippian (Visean) ; Ireland.

DIAGNOSIS. — Colony small, basket-shaped, with obverse surface on exterior surface. Branches narrow straight to moderately sinuous; dissepiments regularly spaced; fenestrules subrectangular. Two rows of autozooecia per branch; low median keel on obverse side of branch with nodes aligned in single row. Very long spine extends proximally from colony origin; autozooecial chambers small, triangular in deep tangential sections, bean-shaped in shallow endozone; reverse surface of branches smoother (modified from McKinney, pers. comm. April 2011).

OCCURRENCE. — Mississippian; Ireland, France.

COMPARISON

Ptilofenestella Tavener-Smith, 1965 is similar to Spinofenestella Termier & Termier, 1971 in the shape of autozooecia and in presence of median keel with nodes, but differs from it by the basket-shaped colony with long central proximal spine.

Ptilofenestella carrickensis Tavener-Smith, 1965 . ( Fig. 25F )

Ptilofenestella carrickensis Tavener-Smith, 1965: 491 , pl. 66, figs 1-14, text-figs 5-6. — Wyse Jackson et al. 2009: 76-77, fig. 1.

MATERIAL. — TCD.60346, 60347.

OCCURRENCE. — Carboniferous, Mississippian (Visean); Counties Fermanagh and Leitrim, Ireland, Roque Redonde (Montagne Noire, southern France). Mississippian (Brigantian); Loughshinney, Co. Dublin, Ireland ( Wyse Jackson et al. 2009).

DESCRIPTION

Colonies form basket-shaped expansions 4.5 mm high by 5 mm wide, composed of 17 to 20 slightly sinuous branches, joined by short dissepiments. Fenestrules rounded rectangular, about twice as long as wide. Keel low, with a single row of small nodes. Autozooecia arranged in two rows on outer-side of branches, autozooecial apertures circular, 4 to 5 per fenestrule length; autozooecial chambers pentagonal in mid-depth tangential-section. Spine 0.3 mm in diameter developed from proximal portion of colony, broken so full length unknown.

COMPARISON

The specimens from Roque Redonde fall within the range and morphology exhibited in P.carrickensis from the type locality.

Figures

FIG. 25. — A-E, Fabifenestella macrofenestrata n. sp., holotype SMF 21.915; A, mid-tangential section showing autozooecial chambers with hemisepta (arrow); B, tangential section showing autozooecial apertures and apertural nodes; C-E, tangential section showing apparent brooding structures (C, arrow). F, Ptilofenestella carrickensis Tavener-Smith, 1965, TCD.60346; G-I, Polypora dendroides M’Coy, 1844; G, H, mid-tangential section showing autozooecial chambers, SMF 21.920; I, branch transverse section, SMF 21.918. Scale bars: A, B, D, E, H, 0.2 mm; C, G, 0.5 mm; F, G, 2 mm.